Life & Earth Sciences Calculators

Explore models and calculators spanning ecology, hydrology, soils, climate, geoscience and astrophysics. Simulate population dynamics, estimate river flow and groundwater, gauge erosion, convert soil salinity, analyze exoplanet transits, photometry and redshift, and more. Results reflect idealized models—always consider local data, assumptions and uncertainty.

Ecology & Population Biology

Lotka–Volterra (Predator–Prey) Simulator

Explore cyclical dynamics with adjustable α, β, γ, δ parameters.

Island Biogeography Calculator

Equilibrium species richness from colonization and extinction rates.

Niche Breadth Calculator

Compute Levin’s or Shannon-based niche width from resource use.

Population Pyramid Generator

Build age–sex distributions from counts or proportions.

Life Table Calculator

lx, qx, ex and survivorship metrics from cohort data.

Biophysics & Transport

Fick’s Law of Diffusion

Flux through membranes from gradients, area and diffusivity.

Hydrology & Hydrogeology

River Discharge (Velocity–Area)

Q = A·v with section geometry and mean velocity methods.

Darcy’s Law Groundwater Flow

Specific discharge from hydraulic gradient and conductivity.

Aquifer Drawdown (Theis)

Confined aquifer response to pumping via Theis solution.

Soils & Agroecology

Soil Salinity (EC) Conversion

Convert EC units (dS/m, mS/cm, µS/cm) and estimate TDS.

Crop Evapotranspiration (ETc)

ETc = Kc × ETo with stage-specific crop coefficients.

Universal Soil Loss Equation (USLE)

A = R·K·LS·C·P annual erosion estimate by factor inputs.

Climate & Ocean Science

Greenhouse Gas Warming Potential (GWP)

CO₂e over 20/100/500-year horizons for common gases.

Ocean Acidification (pH)

pH/Ω estimates from DIC/TA or CO₂ changes (simplified).

Astronomy & Astrophysics

Astronomical Redshift (Doppler)

z from Δλ/λ or radial velocity (non-relativistic & relativistic).

Apparent & Absolute Magnitude

Distance modulus, luminosity and extinction adjustments.

Exoplanet Transit Depth

δ ≈ (Rₚ/R★)² with limb-darkening option.

Stellar Evolution Calculator

Main sequence lifetime and stage estimates by mass/metallicity.

Geoscience & Geochronology

Plate Tectonics Velocity

Relative plate speeds from great-circle motion parameters.

Carbon Dating Calculator

Radiocarbon age from ¹⁴C activity with half-life options.